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Quantum Melting of the Charge Density Wave State in 1T-TiSe2

C. S. Snow·J. F. Karpus·S. L. Cooper·T. E. Kidd·T. -C. Chiang
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Abstract

We report a Raman scattering study of low-temperature, pressure-induced melting of the CDW phase of 1T-TiSe2. Our Raman scattering measurements reveal that the collapse of the CDW state occurs in three stages: (i) For P<5 kbar, the pressure dependence of the CDW amplitude mode energies and intensities are indicative of a ``crystalline'' CDW regime; (ii) for 5 < P < 25 kbar, there is a decrease in the CDW amplitude mode energies and intensities with increasing pressure that suggests a regime in which the CDW softens, and may decouple from the lattice; and (iii) for P>25 kbar, the absence of amplitude modes reveals a melted CDW regime.

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C. S. Snow, J. F. Karpus, S. L. Cooper, T. E. Kidd, T. -C. Chiang. 2003-04-11. Quantum Melting of the Charge Density Wave State in 1T-TiSe2. https://doi.org/10.1103/physrevlett.91.136402

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